Biology subjects

Sahoo, M.

Publications and source records attributed to Sahoo, M..

5 recordsLinked to original sources

bioRxiv2022

Association of polymorphisms of IL-6 pathway genes (IL6, IL6R and IL6ST) with COVID-19 severity in an Amazonian population.

Interleukin-6 have been recognized as a major role player in COVID-19 severity, being an important regulator of cytokine storm. Hence, the evaluation of the influence of polymorphisms in key genes of IL-6 pathway, namely IL6, IL6R and IL6ST, may provide valuable prognostic/predictive biomarkers on COVID-19. The present cross-sectional study genotyped three Single Nucleotide Polymorphisms - SNPs (rs1800795, rs2228145 and rs7730934) at IL6, IL6R and IL6ST genes, respectively, in 227 COVID-19 patients (132 hospitalized and 95 non-hospitalized). Genotype frequencies were compared between these groups. As control group, published data on gene and genotype frequencies was gathered from published studies from before the pandemic started. Our major results point to an association of IL6 C allele with COVID-19 severity. Moreover, IL-6 plasmatic levels were higher among IL6 CC genotype carriers. Additionally, the frequency of symptoms was higher at IL6 CC and IL6R CC genotypes. In conclusion the data suggest an important role of IL6 C allele and IL6R CC genotype on COVID-19 severity, in agreement with indirect evidences from literature about association of these genotypes with mortality rates, pneumonia, heightening of protein plasmatic levels proinflammatory driven effects.

genetics↗

bioRxiv2021

Infection and vaccine-induced neutralizing antibody responses to the SARS-CoV-2 B.1.617.1 variant

SARS-CoV-2 has caused a devastating global pandemic. The recent emergence of SARS-CoV-2 variants that are less sensitive to neutralization by convalescent sera or vaccine-induced neutralizing antibody responses has raised concerns. A second wave of SARS-CoV-2 infections in India is leading to the expansion of SARS-CoV-2 variants. The B.1.617.1 variant has rapidly spread throughout India and to several countries throughout the world. In this study, using a live virus assay, we describe the neutralizing antibody response to the B.1.617.1 variant in serum from infected and vaccinated individuals. We found that the B.1.617.1 variant is 6.8-fold more resistant to neutralization by sera from COVID-19 convalescent and Moderna and Pfizer vaccinated individuals. Despite this, a majority of the sera from convalescent individuals and all sera from vaccinated individuals were still able to neutralize the B.1.617.1 variant. This suggests that protective immunity by the mRNA vaccines tested here are likely retained against the B.1.617.1 variant. As the B.1.617.1 variant continues to evolve, it will be important to monitor how additional mutations within the spike impact antibody resistance, viral transmission and vaccine efficacy.

immunology↗

bioRxiv2020

Inferring Toll-Like Receptor induced epitope subunit vaccine candidate against SARS-CoV-2: A Reverse Vaccinology approach

Toll-Like Receptors (TLRs) are a group of Pattern Recognition Receptors (PRRs) which bind to the exogenous pathogen associated molecular patterns (PAMPs) like other PRRs; hence the main function is to sense the harmness and mediate the innate immune response to pathogens. TLRs play an important role in innate immune responses to infection. The host has evolved to use other TLR and PAMP agonists as agents to stimulate a protective inflammatory immune response against infection. Because only a small number of doses are given, TLR agonists appear to have greater potential and fewer safety concerns than other uses as vaccine adjuvants. In the present days, development of peptides targeting immune response can be approved for survival in biological monitoring systems before vaccine exposures. Peptide vaccines are easy to synthesize, more stable and relatively safe. In addition, production of peptides becomes simple, easily reproducible, fast and cost effective. Getting vaccinated against Covid-19, which has become a pandemic in the human population, is the most practical way to control the outbreak. The new coronavirus does not contain a drug or vaccine to prevent it from spreading to humans. To getting a proper vaccine candidate against the novel coronavirus, the present study used the reverse vaccinology approach by using a complete set of SARS-CoV-2 proteins; such as: Spike, Envelope, Nucleocapsid, Membrane, NSPs, and ORFs to extract the antigenic elements that produce B-cell, T-cell and IFN positive epitopes. These epitopes with precise binding to the Toll-Like receptors (1-10) have developed epitope based vaccine candidates. We have prioritized a set of epitopes based on their antigenicity, allergenicity, sequence conservation and projected population coverage world-wide. The selected epitopes were employed for in-silico docking interactions with Toll-Like receptors and molecular dynamic simulation confirmed the stability of the vaccine candidates resulting epitope of spike proteins with both the TLR 7 and 8 shows the best binding affinity. We believe that this ideal epitope vaccine candidate could enhance the immune response of the host and reduce the reinfection risk.

bioinformatics↗

bioRxiv2020

High throughput detection and genetic epidemiology of SARS-CoV-2 using COVIDSeq next generation sequencing

The rapid emergence of coronavirus disease 2019 (COVID-19) as a global pandemic affecting millions of individuals globally has necessitated sensitive and high-throughput approaches for the diagnosis, surveillance and for determining the genetic epidemiology of SARS-CoV-2. In the present study, we used the COVIDSeq protocol, which involves multiplex-PCR, barcoding and sequencing of samples for high-throughput detection and deciphering the genetic epidemiology of SARS-CoV-2. We used the approach on 752 clinical samples in duplicates, amounting to a total of 1536 samples which could be sequenced on a single S4 sequencing flow cell on NovaSeq 6000. Our analysis suggests a high concordance between technical duplicates and a high concordance of detection of SARS-CoV-2 between the COVIDSeq as well as RT-PCR approaches. An in-depth analysis revealed a total of six samples in which COVIDSeq detected SARS-CoV-2 in high confidence which were negative in RT-PCR. Additionally, the assay could detect SARS-CoV-2 in 21 samples and 16 samples which were classified inconclusive and pan-sarbeco positive respectively suggesting that COVIDSeq could be used as a confirmatory test. The sequencing approach also enabled insights into the evolution and genetic epidemiology of the SARS-CoV-2 samples. The samples were classified into a total of 3 clades. This study reports two lineages B.1.112 and B.1.99 for the first time in India. This study also revealed 1,143 unique single nucleotide variants and added a total of 73 novel variants identified for the first time. To the best of our knowledge, this is the first report of the COVIDSeq approach for detection and genetic epidemiology of SARS-CoV-2. Our analysis suggests that COVIDSeq could be a potential high sensitivity assay for detection of SARS-CoV-2, with an additional advantage of enabling genetic epidemiology of SARS-CoV-2.

genomics↗

bioRxiv2017

Metagenomic DNA sequencing for the diagnosis of intraocular infections

PurposeTo compare the performance of unbiased high-throughput sequencing with pathogen directed PCR using DNA isolated from archived ocular fluid, approaches that are compatible with the current sample handling practice of ophthalmologists.\n\nDesignRetrospective molecular study of banked vitreous samples.\n\nMethodsWe evaluated a metagenomic DNA sequencing-based approach (DNA-seq) using archived positive (n = 31) and negative (n=36) vitreous specimens as determined by reference pathogen-specific PCR assays (herpes simplex virus 1 and 2, cytomegalovirus, varicella-zoster virus, and Toxoplasma gondii). Pathogens were identified using a rapid computational pipeline to analyze the non-host sequences obtained from DNA-seq. Clinical samples were de-identified and laboratory personnel handling the samples and interpreting the data were masked.\n\nResultsMetagenomic DNA sequencing detected 87% of positive reference samples. In the presumed negative reference samples, DNA-seq detected an additional 6 different pathogens in 8 samples (22% of negative samples) that were either not detected or not targeted with pathogen-specific PCR assays. Infectious agents identified only with DNA-seq were Candida dubliniensis, Klebsiella pneumoniae, human herpesvirus 6 (HHV-6), and human T-cell leukemia virus type 1 (HTLV-1). Discordant samples were independently verified in CLIA-certified laboratories. CMV sequences were compared against the antiviral mutation database and 3 of the samples were found to have mutations conferring ganciclovir resistance.\n\nConclusionsMetagenomic DNA sequencing was highly concordant with pathogen-directed PCRs. The unbiased nature of metagenomics DNA sequencing allowed an expanded scope of pathogen detection, including bacteria, fungal species, and viruses, resolving 22% of cases that had previously escaped detection by routine pathogen-specific PCRs. The detection of drug resistance mutations highlights the potential for unbiased sequencing to provide clinically actionable information beyond pathogen species detection.

genomics↗